BaZi Calculator

Calculate a person’s Four Pillars (BaZi / Eight Characters) from birth date and time using sexagenary-cycle offsets from one trusted reference datetime that already has known year/month/day/hour pillars. Also calculate DaYun (10-year luck cycles) when gender is provided, and include the current LiuNian (流年) Ganzhi. Use when user asks for BaZi pillars, eight characters, stem-branch pillar calculation, DaYun, or current LiuNian.

Calculate Year/Month/Day/Hour pillars with a single reference point.

Quick Start

1. Use references/reference-verified.json (or your own verified reference JSON) with one trusted reference datetime and its four pillars.
2. Run:

python3 scripts/calc_bazi.py \
  --birth "1992-08-14 21:35" \
  --tz "Asia/Shanghai" \
  --reference references/reference-verified.json \
  --gender male

3. Return results left-to-right as:

• Hour pillar
• Day pillar
• Month pillar
• Year pillar
• Eight characters (Hour Day Month Year)

Workflow

1) Validate inputs

• Require birth datetime (YYYY-MM-DD HH:MM).
• Require timezone (default Asia/Shanghai if omitted).
• Require one reference JSON with:
  • reference_datetime
  • reference_pillars.year/month/day/hour

2) Compute offsets from reference

• Year offset: LiChun-adjusted year difference (approximation: Feb-04 00:00 local).
• Month offset: calendar month difference.
• Day offset: calendar day difference.
• Hour offset: 2-hour bin difference (Zi starts at 23:00).

3) Shift each base pillar in 60-cycle

• target_pillar = shift(reference_pillar, offset mod 60) for year/month/day/hour separately.

4) Present output

Birth (local): 1992-08-14 21:35 (Asia/Shanghai)
Hour Pillar: 丙戌
Day Pillar: 癸亥
Month Pillar: 丙申
Year Pillar: 壬申
Eight Characters (L→R Hour/Day/Month/Year): 丙戌 癸亥 丙申 壬申

Notes

• This is a deterministic reference-based method.
• Accuracy depends on correctness of the chosen reference and boundary rules.
• For professional-grade astrology, validate solar-term boundaries and true solar time adjustments.